Martha will have done something with a key and will be on Earth at the end.

Let's take these one at a time:

Tennant was the Doctor at the end. Survived by zapping the hand. Yep... cheap (and what soppiness with Rose?!)

Donna's not dead, but she may as well be as part of the 'Who' universe.

Yep, she's gone. 'Permanently' (didn't they say that before?).

Jack survives incineration and extermination (not necessarily in that order).

Gwen and Ianto hid in a cupboard thanks to Tosh's 'from out of nowhere a solution appears' timelock device. Oh dear.

Martha didn't do anything with a key. She threatened to.

Overall, some enjoyable stuff in the episode (I particularly liked the multilingual daleks) - but there were half a dozen too many conveniences to get them out of a whole, though I appreciated Davros not being seen to be destroyed. In 'Confidential', Billie Piper said something like 'that's what is great about SF is that anything can happen'. No Billie, if anything can happen it cheats your audience by removing internal logic and you have fantasy.

As a season, there were some really nice things - but there has been an over-reliance on mysticism which I'd like to see reduced dramatically.

So, tonight is the final episode of Dr. Who for a while (except for the Christmas specials).... and amazingly the fate of the Doctor is still a mystery after he began to regenerate last week. (I'm assuming that by now, people will have seen 'Stolen Earth' if they were at all interested - this will only contain speculations, I have no insider knowledge about today's episode).
So they're in a bit of a pickle.

The Doctor - by the end of the episode, it will be David Tennant. This will seem cheap.

I think that Donna will sacrifice herself in some ill-explained techspeak way to prevent the regeneration because the world needs the doctor. Not just any doctor but this doctor. A new regeneration would be disoriented for a critical time. This will involve the hand in a jar that keeps being shown. I did flick around the TV the other night, and saw James Nesbitt on Graham Norton's chat show (repeated tomorrow) along with Catherine Tate... coincidence? I don't know - I saw that it was Graham Norton and changed channels. (It wasn't 'Nancy'!). I would rather have the regeneration - that'd be special as it implies that the BBC somehow managed to pull off a brilliant feat of keeping a secret - and it also would be true to the history of regenerations.

Jack will go storming off and get himself into trouble. Which he'll survive by virtue of being Captain Scarlet, sorry, Harkness.

Sarah Jane will survive - this has been seen on the trailers. This implies that the Daleks who saw her in the car for some reason say 'We won't EXTERMINATE you after all, come with us so we can EXTERMINATE you later...'

Rose - I'm unsure about Rose. I can't imagine her coming back as a regular, it'd place too much importance on the assistant above the Doctor. I can imagine her being 'sucked back to the parallel world' once things are put to rights - though this'd be silly. I can also imagine her not surviving.

It's a shame that Dempsey aka Michael Brandon, was killed. He could have made a decent recurring character as Unit Boss. Of course, we don't actually see him killed, so although I don't think we'll see him again in Journey's End, he could come back if they wanted. I don't think this'll happen though.

Davros - he needs to escape. The Daleks have been wiped out only to come back several times. If Davros escapes he can rebuild. If he doesn't then incredulity is stretched once more once the Daleks reappear.

Gwen and Ianto - now, I think they're safe as to kill them outside the Torchwood storyline would not seem reasonable to me (though, admittedly the number of folks who watch Torchwood without Who will be limited). They're in a tough spot with Daleks coming into the base. Perhaps they'll hide in a cupboard or something.

If Davros can return from the Time War era, can the Timelords?

The shadow proclamation people will probably show up with the Judoon (Mo Ho Ro Sho Bo... Po!) This will not be in good time - at best, it'll be just in time.

So to summarise:

Doctor will be Tennant. This'll probably seem cheap.

Donna will be Dead

Rose will be Gone

Jack will survive (Face of Bo, remember)

Gwen and Ianto will be playing Sardines

Martha will have done something with a key and will be on Earth at the end.

Hopes:

The doctor actually regenerates, and we marvel at how well they kept the secret.

Davros survives.

Bernard Cribbins for new assistant! Old guys have been seriously under-represented in the Tardis of late.

Seriously - do all the assistants have to be from modern day Earth? Surely the audience could cope with a wider pool to select from. Preferably one who is an orphan with no dependents left at home.

Most importantly, it doesn't suck.... the first part of last week's was a little sucky in an 'everything but the kitchen sink' kind of way, but it was saved by the final 20 minutes or so.

For the future, will the people of Earth continue to be surprised when Aliens land and try to destroy them all?

Edward J.R. suggests there'll be two doctors. (I did consider that above, but I had heard that during the week and so chose to ignore it - it does seem like a possible 'get out of jail' clause - though the energy needed to create the mass of a second doctor would be huge.... unless you have direct re-shaping of another mass - bye bye donna?)

The episode will be screened in Trafalgar Square tonight. Freema Aygeman will be present. If planning to attend, be warned that the same was planned last year but it was cancelled (but this year we have iplayer, so the risk might be worth taking!)

L7 World has an interesting take on which companion will die.... it seems a convincing argument, but would surely be a show-stopper if it were permanent? However, with the title of the show being what it is - this seems like a good guess (but it cannot be a permanent death, surely). The get-out would have to be the return of the Time Lords so that a new Tardis could be obtained....

Well, it's not Jack. For one thing, he can't die, and for another, there's the aforementioned series three of Torchwood.

It's also unlikely to be Sarah Jane, for all the reasons previously stated. (Although the label "most loyal" would be appropriate.).

It's probably not Martha. I'm not sure she would warrant "most loyal" for one thing (although she did traipse about the earth for a year, that probably nabbed her some loyal-points). But also, she has a new life, a new man and really the Doctor's cocked up her life enough as it is. I mean, I kind of hope it'd be Martha, if only for the fact that I don't like her as much as everyone else on this list, but there's the facts..

Hopefully not Rose. It would just be too cruel to bring her back on the show only to kill her off. Like, really really harsh. And just think of all the small children (and raging fangirls) who would just be crushed. Also I was surfing about YouTube today and found a Jonathan Ross interview with Billie Piper right after she'd gone off the show, and she just seemed so wistful about leaving and she had her reasons, but I have this small hope that now she's back at least through the 2009 specials. And then we'll see. And also I really think she wouldn't want to leave it so... final. And I don't know how they would possibly have the Doctor recover from that.

So that leaves Donna. And as much as I hate the fact, I think them's the breaks. And what's more, I'm not sure how her story would end otherwise. Unless they find her library-boyfriend and she ends up living in the 51st century, happily ever after. Unfortunately, it seems a remote possibility, but I don't think she'll ever be satisfied with anything else after running with the Doctor. And maybe there's supposed to be a false sense of security since she already committed the ultimate sacrifice at the end of "Turn Left", but I don't think that leaves her safe at all. If anything, I think it leaves her more vulnerable than anyone. She was already told she was going to die, and she's not dead yet. Plus the woman at the Shadow Proclamation expressed her condolences on the loss yet to come. I think Donna's shit out of luck.

Yep - that seems spot on to me.

Well, in a few hours we'll know.... and I'll either look like a prophet, or incredibly naïve - but if the latter, do remember that I won't be alone. If I was right, you can be duly impressed. If wrong, you can assume that everyone speculating was doing it wildly and that those people who were right just got lucky.